This invention relates to systems for packing cartons into containers or cases, and more particularly, to a machine and process for stacking and loading articles such as egg cartons or trays into shipping containers.
Processing and packaging of eggs has become highly automated over recent years, with many functions which were accomplished manually now being performed either completely or partially automatically. Associated with this change are the high speeds attained in the various processing steps including, washing, grading and packaging of the eggs into individual cartons. The egg cartons, once filled with eggs are then ready for shipment to, for instance, a supermarket.
In this regard, it is conventional for the egg cartons to be stacked three abreast with each layer being rotated with respect to the adjacent layer or layers. The cartons thus arranged are placed into a shipping container, the stack of cartons generally including six layers or rows. A shipping container is thus provided with eighteen cartons of eggs.
With the high speeds attained in egg processing, a great deal of manual effort is expended in stacking and filling the shipping container. While stacking and unstacking machines have been developed, the industry, to a large extent, continues to perform this function manually.
A prior art container loading machine is disclosed in U.S. Pat. No. 4,104,846. A system is provided by which the egg cartons are conveyed to a loading zone and subsequently to a discharge carriage. In this system, successive layers of egg cartons are stacked by loading subsequently higher layers of egg cartons upon lower layers, each of which is lowered by rods a predetermined distance. Thus, a complex mechanism is provided for arranging a first egg carton layer which is lowered by a predetermined uniform amount which corresponds precisely to the height of an egg carton, before each subsequent layer of egg cartons is placed thereon.
An object of this invention is to provide an improved case packing system of the above-described type.
Another, more particular object of this invention is to provide such an improved case packing system which is adapted to receive egg cartons or trays travelling on a conveyor belt and to lift a stack of such egg cartons or trays into a container.
A further particular object of this invention is to provide a system whereby layers of articles to be stacked can be arranged in several possible configurations having predetermined angular relationships with respect to one another.
It is a still further object of this invention to provide a case packing system which recognizes the articles to be stacked and provides a selection between acceptable and unacceptable articles to be packed.